Lifting tongs



April 6, 1937.

A. CAMEROTA ET AL 2,076,494

LIFTING TONGS 5 Sheets-Sheet '1 Filed March 20, 1936 INVENTORS: 7 Loans9. Camzmta &

ORNEYS.

April 6, 1937.

L. A. CAMEROTA Ef L 2,076,494

LIFTING TONGS 5 Sheets-Sheet, 2

Filed March 20, 1936 INVENTORS: is fiL'amzroi/a 5 701m milack TORNEYSWITNESSES:

Lou

April 6, 1937. I A. CAMEROTA ET AL I 2,076,494

LIFTINGTONGS Filed Mai-ch 20, 1956 5 SheetSheet 5 FIG: I

WITNESSES: INVENTORS:

I 1 TORNEYS.

April 6, 1937.

WITNESSES:

L. A. CAMEROTA ET AL 2,076,494

' 'L IFTING TONGS 5 Sheets-Sheet 5.-

Filed March 20, 1936 INVENTORS! Laws .6? L'mmemtazz RNEYS.

; By John Mail/adv,

Patented Apr. 6, 1937 UNIT STATES PATENT OFFICE LIFTING TONGSApplication March 20, 1936, Serial No. 69,804

16 Claims.

Our invention relates generally to lifting tongs and more particularlyto flask hooks, though it is obviously applicable to the lifting andtransporting of various other heavy objects. Our par- 5 ticularinvention is directed to the handling of hot flasks used in pipecasting. The task of engaging and disengaging lifting hooks with hotflasks is recognized as both diflicult and dangerous when done by a manstationed at the flasks. The danger from molten metal to the manoperating the hooks at the flask is great. The delays in handlingbecause of the slow and awkward manual operation in engaging anddisengaging the hooks are costly and retard the plant production,particularly when flasks are handled in pairs or larger groups.

Consequently one of the objects of our invention is the avoidance ofthis unnecessary, dangerous and slow manual labor in disengaging andengaging flask hooks by making the operation automatic to the extentthat it is controlled and performed by the crane operator by themanipulation of his hoisting controls. A further object of our inventionis the provision of such a device for handling the cylindrical pipeflasks in groups instead of singly. Effectiveness, speed andpositiveness of action, and reliability are also objectives to which ourinvention is directed. Other objects and advantages will be apparentfrom a detailed description of a preferred embodiment thereof whichfollows and which has reference to the accompanying drawings of which:

Fig. I is a front elevation of a lifting device.

Fig. II is an end view of a lifting device.

Fig. III is a plan view of the same.

Fig. IV is a central section of the lifting device about to be loweredover a pair of pipes.

Fig. V is a view similar to Fig. IV showing the parts in a difierentposition.

Fig. VI is a View similar to Fig. IV showing the device carrying a pairof pipes; and

Fig. VII is a simplified form of the device for carrying a single pipe.

For the purposes of a detailed description of 45 the device shown in thedrawings that device may be resolved into the following elements:operating tongs I, follower tongs 2, side members 3, operating arms 4,head 5, suspension member 6, spreaders 7, connecting rods 8, andspreader 50 hook H.

The hook-like tongs l and 2 are pivotally supported by the side members3 between an inner element l3 and an outer element M of the side members3. The outer element M at each end 55 of the device has supporting legs15 which take the weight of the device when resting on the groundinstead of the tongs l and 2 and without interfering with pipe flasks l0being transported. The tongs l and 2 work on pivot rods l6 which extendthe length of the device between the two side members 3.

For each operating tong I there is a follower tong 2 to which it ispivotally joined by the connecting rod 8. There is an operating tong land a follower tong 2 in each pair of tongs and the operating tong l ofone pair is connected to the corresponding follower tong 2 of the otherpair. Thus the right hand members of each pair of tongs are movedtogether according to the motion of the actuating tong I and the lefthand members operate in a like manner. The inner elements l3 and theouter elements l4 of the side members 3 are separated by spacing rods 23to allow the free pivotal operation of the tongs i and 2; the sidemembers 3 at each end of the device are also spaced by the spacing rods20.

Each tong I has an operating arm 4, which is made upof upper and lowerpieces 22 and 23 and pivotally joined by integrating rods 24 and 25respectively. The rods 24 and 25 join the pivotal points ofcorresponding operating arms 4 on each end of the device. The operatingarms 4 at the same end of the device are pivotally connected to the head5 by means of a bolt 29v supported by brackets 21 which are fastened tothe top of the head 5. The upper parts of the operating arms 4 arecurved in an obvious manner to allow them to close without interferencefrom the head 5.

Pivotally attached to the corresponding operating arms 4 at each end ofthe device are spreaders l which are joined at their outer ends byintegrating rod 28 secured with nuts. These spreaders I are mounted onthe rod 24 but obviously could be attached to the arms-4 in other waysand at other points. Each spreader T has formed in its underside anengagement element IS in the form of a notch for engaging rod 25. Therod 25 functions as a'stop which the spreaders I ride on and fall intoengagement with. The spreaders l are curved downwardly from the ends inorder to prevent interference by contact with the head 5 at the centralportions of the spreaders 'l.

The spreader hook I l is pivotally attached to a bracket 32 which isattached to the suspension member 6. At the lower end of the hook H is aguiding surface 33 which-engages an integrating 'rod 34 secured betweenthe spreaders l as the suspension member 6 is lowered. This guidingsurface 33 is designed to guide the rod 34 into hooking engagement withthe hook II by causing the hook II to swing away from the vertical asthe suspension member 6 is lowered until the hook I I slips back intoplace under the rod 34. It is important that the hook II at no timeengage the rod 34 on the side of the hook I I opposite from the guidingsurface 33. Consequently the upper portion 36 of the hook II is extendedinward toward the suspension member 6 and the engagement of the portion36 with the suspension member 6 prevents the hook I I from swinging intoa position beyond the rod 34.

The head 5 is of heavy construction and is made up of two strongchannels 3'! riveted to a central plate 38 to form an I-beam. At themiddle of the head 5, the suspension member Ii is positioned withcapacity for limited vertical movement. The suspension member 6 extendsaround the head 5 and is composed of side plates'40- secured to toppieces M and to a bottom piece 43. The top pieces 4I separated by an eyepiece make up the top piece, with rivets 44 passing through all three ofthese pieces. Removable bolts attach the side plates 40 to the bottompiece 43. On each side of the suspension member 6 are guide brackets 45attached to the head 5. These guide brackets 45 guide the suspensionmember 6 in the longitudinal plane of the device while the slidingcontact of the plates 40 with the flanges of the channels 3'! guide itin the transverse plane. A strengthening piece 46 is riveted to eachside of the head 5 at its central portion.

The simplified form of this device shown in Fig. VII handles but onepipe: flask Ill at a time; the construction is clearly understandablefrom the above description of the two-flask type. In the simplified formthere are no follower tongs 2 and no connecting rods 8, but otherwisethe construction is the same as the two-flask type.

In describing the operation of our device it will be assumed that thereare two pipe flasks on the ground awaiting transportation. The liftingtongs are braced in their open position by lowering the head 5 andsuspension member 6', while the device is on the ground, until thespreaders I become locked in engagement with rod 25, as shown in Fig.11. As the device is raised by a crane or other hoisting means the tongsI and 2 remain in the open position because of the bracing action of thespreaders 'I. The crane operator then lowers the device over the twopipe flasks I0 as shown in Fig. IV until the legs I 5 of the device reston the ground straddling the flasks. The suspension member 6 is furtherlowered by the crane operator until the spreader hook II drops into itsengagement position under the rod 34 as shown in Figs. II and V. Thedevice is now lifted and the hook II lifts the spreaders I out ofengagement with the rod 25 allowing the operating arms 4 to operate andclose the tongs I and 2 about the flasks III, as shown in Fig. VI. Theoperating arms 4 operate the operating tongs I which in turn operate thefollower tongs 2 through the connecting rods 8. The device and flasksIII are now lifted and transported by the crane operator to the place ofdeposit where he lowers the device and pipe flasks I0 onto the groundfurther lowering the suspension member 6 and the head 5 until thespreaders 'I again engage the rod 25. The crane operator now agitatesthe suspension member 6 causing the spreader hook II to swing clear ofthe rod 34 at which moment the operator skillfully lifts the suspensionmember 6 and completely disengages the spreader hook I I from the rod34. The weight in the end of the spreader hook II facilitates thisoperation On the part of the crane operator and with a little practicethe operation can be performed easily and quickly by the skilled craneoperator. Once the spreader hook II is thus disengaged the craneoperator may lift the device in its open position clear of the depositedpipe flasks Ill and his task is completed, the device being braced inits open position ready for engagement with other pipe flasks I0.

Thus our invention provides efficient lifting tongs for the handling ofpipe flasks without endangering operators near the hot flasks. Dangerousand slow manual labor is eliminated and control placed inthe hands ofthe crane operator. A

. plurality of flasks may be efliciently handled at one time and it isobvious from the above described apparatus that additional tongs may beincluded in a modification of the device for the handling of more thantwo pipe flasks. The operation of this device is simple and positivewith no danger of dropping the pipe flasks once engagement has beenaccomplished.

While we have described the preferred form of our invention with also asimplified form thereof, in some detail, it will be obvious to oneskilled in the art that numerous changes and modifications can be madein the device as described without departing from the spirit of ourinvention as pointed out and claimed in the following claims.

Having thus described our invention, we claim:

1. A lifting device comprising a head, operating arms pivotally attachedto the head, said operating arms including pivotally attached upper andlower members, tongs formed on the lower members and pivotally connectedto operate as a pair, a spreader pivotally attached at one end to one ofthe operating arms and restingon a stop member attached to the other ofthe arms, said spreader having an engagement means for engaging saidstop member, and a suspension member movably attached to the head andcarrying a spreader hook to automatically engage the spreader when thesuspension member is in the down position.

2. A lifting device according to claim 1 characterized further by thefact that the spreader is pivotally attached to one of the arms at thejuncture of its upper and lower member, that the stop on which thespreader rests is positioned at the juncture of the upper and lowermembers of the other arm, and that the spreader is curved downwardlyfrom the ends.

3. A lifting device according to claim 1 characterized further by thefact that the suspension member is attached to the head with capacityfor guided vertical movement and the end of the spreader hook isinclined to guide the hook into engagement with the spreader.

4. A lifting device according to claim 1 characterized further by thefact that the spreader has a hooking member for engagement with thespreader hook.

5. A lifting device comprising an elongated head, operating armspivotally attached at each end of the head, said'operating armsincluding pivotally attached upper and lower members, tongs formed onthe lower members and pivotally connected to operate in pairs,integrating rods connecting the corresponding arms at the ends of thehead to operate integrally, a spreader pivotally attached at one end tothe arms on one side of the head and resting on a stop member attachedto the arms on the other side of the head, said spreader having anengagement means for engaging said stop member; and a suspension membermovably attached to the central portion of the head and carrying aspreader hook to automatically engage the spreader when the suspensionmember is in the down position.

6. A lifting device according to claim 5 characterized further by thefact that there is an additional spreader joined to the first mentionedspreader by rods, and the stop on which the spreader rests is also a rodextending between two arms at opposite ends of the device.

7. A lifting device according to claim 5 characterized by the furtherfact that the integrating rods form the pivots by which the upper andlower sections of the arms are joined, and that the spreader ispivotally attached to one of these integrating rods and rests on theother as a stop member.

8. A lifting device comprising a beam-like head, operating armspivotally attached at each end of the head, said operating armsincluding pivotally attached upper and lower members, tongs formed onthe lower members and pivotally connected to operate in pairs,integrating rods connecting the pivots of the corresponding arms at theends of the head to operate integrally, curved spreaders pivotallyattached at one end to the integrating rod joining the pivots of thearms on one side of the head and resting on the integrating rod joiningthe pivots of the arms on the other side of the head, said spreadershaving engagement notches on their undersides and being joined byintegrating rods, a suspension member attached to the central portion ofthe head with capacity for vertical guided movement, and a spreader hookwith a guiding surface at its end attached to the suspension member toautomatically engage one of the integrating rods between the spreaderswhen the suspension member is in the down position.

9. A lifting device comprising an elongated head, a pair of operatingarms pivotally attached at each end of the head, said operating armsincluding pivotally joined upper and lower members, integrating rodsconnecting the arms on each side of the head, operating tongs formed onthe lower members, said operating tongs at each end of the head beingthe opposing members of a pair and operating in opposite directions,side members pivotally joining the operating tongs at each end of thehead, follower tongs pivotally attached to the side members in pairswith the operating tongs, connecting rods joining the operating tongs tocorresponding follower tongs on each side piece, a spreader pivotallyattached at one end to the arms on one side of the head and resting on astop member attached to the arms on the other side of the head, saidspreader having an engagement notch for engaging said stop member, and asuspension member movably attached to the central portion of the headand carrying a spreader hook to automatically engage the spreader whenthe suspension member is in the down position.

10. A lifting device according to claim 9, characterized further by thefact that said side members are interconnected by integrating rods.

11. A lifting device according to claim 9 characterized further by thefact that said side members extend below the operating tongs in allpositions thereof, and that said side members have formed therein workopenings aligned with the pairs of tongs.

12. A lifting device according to claim 9 characterized further by thefact that there is an additional spreader attached to the firstmentioned spreader by integrating rods and that one of the spreaderintegrating rods is in line with said spreader hook for engagementtherewith.

13. A lifting device according to claim 9 characterized further by thefact that the suspension member is movably attached to. the head withcapacity for guided vertical movement and that the spreader hook issuspended over the spreader and has a guiding surface formed on itslower end.

14. A lifting device comprising a head, a pair of operating armspivotally attached to the head, said operating arms including pivotallyjoined upper and lower members, opposing operating tongs formed on thelower members, side members pivotally joining the operating tongs,follower tongs having operating levers and pivotally attached to theside members in pairs with the operating tongs, connecting rods joiningthe operating tongs to corresponding follower tongs, a spreaderpivotally attached at one end to an operating arm and resting on a stopattached to the other operating arm, said spreader having an engagementnotch for engaging the stop, and a suspension member movably attached tothe central portion of the head and carrying a spreader hook toautomatically engage the spreader in the down position of the suspensionmember.

15. A lifting device comprising a head, interconnected grappling tongs,operating arms connecting the head and tongs, a substantiallyhorizontally disposed movable spreader for locking the operating armswith the tongs in an open position, said spreader having capacity formovement to unlock said operating arms, a suspension member movablyattached to the head and having a spreader hook for engaging thespreader in the down position of the suspension member.

16. A lifting device comprising a head, interconnected grappling tongs,operating arms connecting the head and tongs for pulling the tongs shutwhen lifted, a movable spreader means for automatically keeping thegrapping tongs open when empty, said spreader having capacity to swingto an inoperative position to allow the grappling tongs to close, meansfor operating said movable spreader means according to the suspensionposition of the lifting device, whereby the tongs are locked open in onesuspension position and open freely in another suspension position.

LOUIS A. CAMEROTA. JOHN MATLACK.

